hi,

we recieved today all sensors for our gasboards.

as a software developer for UAV (drone) we start with the co2 sensor. our goal is a flying chemical sensor uav. here is a first picture of our uav (currently you will see the video option)

http://onlinelib.de/temp/rebotnix/f8p_headers.jpg

right now we have absolut no idea which value in the GAIN for the co2 is usefull.

if anyone can explain how to use the co2 sensor that would be great.

with a gain of 5 we got these range:
1.3709677457
1.3580644130
1.3580644130
1.3870967674
1.3580644130
1.3612903356
1.4322580337
1.3548387289

here are is what we have done:

void setup()
{
// Opening UART to show messages using 'Serial Monitor'
SensorGas.setBoardMode(SENS_ON);
SensorGas.configureSensor(SENS_CO2, 5);
SensorGas.setSensorMode(SENS_ON, SENS_CO2);

USB.begin();


}

void loop()
{
// Blinking LEDs
Utils.blinkLEDs(1000);

// Printing a message, remember to open 'Serial Monitor' to be able to see this message
USB.println("Online...sending sensor data after 3000ms");

// A little delay
delay(3000);

float value = SensorGas.readValue(SENS_CO2);
USB.println(value);

}

thanks for any help and feedback..

best
gary
http://onlinelib.de

Hi gary,

The voltage at the output of the CO2 sensor should be between 220mV and 490mV at a gas concentration of 350ppm. This output voltage will decrease as the gas concentration grows up. The gain stage has been added to allow the user to adjust that output to the input range of the Waspmote.

My advice: calibrate your sensor at the concentration range you desire to measure and set the gain for which the voltage output at the minimum concentration of your range is the nearest possible to 3.3V (the maximum input that Waspmote admits). In case you do not have the possibility of calibrating the sensor in a laboratory, you may estimate the voltage variation using the graph in the data sheet. Usually, a gain of approximately 10 would fit the output range to the input range of the Waspmote, but take into account that the output voltage may change significantly between different sensors, that is why we recommend the calibration.

I hope to have been useful, best regards.

Hi,

thanks for your quick response..that makes all sense for us.

we add today the alcohol tgs2620 and tempature sensor and went thru our park to get some data. All worked every well.

The next step is to add gprs and wireless communication.

Thanks for this great developer device and components.

See ya on cebit in germany.

Best
Gary